J/A+A/704/A225 Polarimetric image of 3C 279 at 22GHz (Toscano+, 2025)
Revisiting 3C 279 jet morphology with space VLBI at 26 microarcsecond
resolution.
Toscano T., Gomez J.L., Zhao G.-Y., Lico R., Fuentes A., Savolainen T.,
Roeder J., Wielgus M., Pushkarev A.B., Traianou E., Zeng A.-L.,
Gurvits L.I., Kovalev Y.Y., Poetzl F.M., Lisakov M.
<Astron. Astrophys. 704, A225 (2025)>
=2025A&A...704A.225T 2025A&A...704A.225T (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Polarization ; Radio sources ; VLBI
Keywords: polarization - techniques: high angular resolution -
techniques: image processing - techniques: interferometric -
galaxies: active - galaxies: jets
Abstract:
We present observations of the blazar 3C 279 at 22GHz using the space
VLBI mission RadioAstron on 2018 January 15. Images in both total
intensity and fractional polarization are reconstructed using RML
method implemented in the eht-imaging library. The electric vector
position angles are found to be mostly aligned with the general jet
direction, suggesting a predominantly toroidal magnetic field, in
agreement with the presence of a helical magnetic field. Ground-space
fringes were detected up to a projected baseline length of
∼8Gλ, achieving the angular resolution of around 26uas. The
fine-scale structure of the relativistic jet is found in our study
extending to a projected distance of ∼180 parsec from the radio core.
However, the filamentary structure reported by previous RadioAstron
observations of 2014 is not detected in our current study. We discuss
potential causes for this phenomenon, together with a comparison using
public 43GHz data from the BEAM-ME program, showing a significant drop
in the jet's total intensity. The optically thick core is observed
with a brightness temperature of 1.6x1012K, consistent with
equipartition between the energy densities of the relativistic
particles and the magnetic field. This yields an estimated magnetic
field strength of 0.2G.
Description:
Polarimetric image of 3C 279 at 22GHz by the space-VLBI mission
RadioAstron on 15 January 2018.
Objects:
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RA (2000) DE Designation(s)
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12 56 11.16 -05 47 21.5 3C 279 = QSO J1256-0547
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 90 1 Information on fits image
fits/* . 1 Individual fits image
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See also:
J/A+A/409/857 : Optical polarization of 3C 279 (Andruchow+, 2003)
J/AJ/133/2866 : 2001-02 optical variability of blazar 3C279 (Kartaltepe+, 2009)
J/ApJ/772/13 : VLBI observations of 3C 279 at 230GHz (Lu+, 2013)
J/A+A/590/A10 : 3C 279 optical photometry and polarimetry (Kiehlmann+, 2016)
J/AJ/151/54 : VRIJHK photometry of 3C 279 (Sandrinelli+, 2016)
J/A+A/630/A56 : A gamma-ray emission zone in 3C 279 (Patino-Alvarez+, 2019)
J/ApJS/245/18 : 9yr R-band photopolarimetric data of 3C 279 (Fraija+, 2019)
J/A+A/640/A69 : 3C 279 Event Horizon Telescope imaging (Kim+, 2020)
J/ApJS/257/37 : Blazars 3C279 and 3C454.3 multiwavelength data (Paliya+, 2021)
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 22 I3 --- Nx Number of pixels along X-axis
24- 26 I3 --- Ny Number of pixels along Y-axis
28- 37 A10 "datime" Obs.date Observation date
39- 43 I5 Kibyte size Size of FITS file
45- 52 A8 --- FileName Name of FITS file, in subdirectory fits
54- 90 A37 --- Title Title of the FITS file
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Acknowledgements:
Teresa Toscano Domingo, ttoscano(at)iaa.es
(End) Patricia Vannier [CDS] 06-Oct-2025